1. Field of the Invention
The present invention relates to an epitaxial growth rate varying method for a side surface of a patterned semiconductor, and particularly to an improved epitaxial growth rate varying method for a side surface of a semiconductor capable of controlling a growth rate of a side surface of a patterned semiconductor by controlling CCl.sub.4 gas when forming an epitaxial layer on a patterned GaAs substrate in a metalorganic chemical deposition method (hereinafter called an "MOCVD"), thus fabricating a desired quantum wire.
2. Description of the Conventional Art
In the industry, a study of an optical device has recently been conducted using compound semiconductor technology. However, very problematic fabrication processes, for example, such as a selective epitaxial technique, have been adopted for fabricating the optical device. However, using the selective epitaxial technique, it is possible to implement a three-dimensional structure of an epitaxial layer with only one growth step without utilization of a complicated device fabrication process. In addition, since a very complicated structure of a device is formed while an epitaxial layer is formed, any damage of a boundary surface during a device fabrication process can be prevented.
Of the above-mentioned epitaxial growth methods, a non-planar growth method is directed to forming a mesa or a V-shaped pattern on a substrate and to growing a desired epitaxial layer. The above-mentioned method has advantages in fabricating a desired device having side surfaces. In addition, it is possible to fabricate a low threshold current laser diode or an optical wave guide with a lower dopant loss.
Recently, a study on fabrication of a quantum wire in the above-mentioned non-planar growth method has been conducted. That is, it was reported that a low threshold current laser diode was fabricated by forming a new moon-shaped quantum wire on a V-shaped groove.
However, when forming a desired structure in the above-mentioned non-planar growth method, the epitaxial thickness, which is related to the vertical direction growth rate of an epitaxial layer, is controlled by the flowing-in amount of a reactive gas or by the time of growth; however, there is no way to control the horizontal direction growth rate (a side surface growth direction of an epitaxial layer).
In the case of MOCVD, it is possible to control the epitaxial layer thickness growth by controlling the Group V/Group III ratio--that is, Group V material amount/Group III material amount-and the growth temperature of the reactive gas. However, a desired performance cannot be achieved. There are no methods at present for controlling the shape and size of the quantum wire when forming a quantum wire on a V-shaped groove since the ratio of horizontal growth rate to vertical growth rate does not exceed 2. Therefore, the growth conditions are disadvantageously subordinated to the inherent growth conditions.